1. Field of the Invention
The present invention relates to an iris identifying apparatus which identifies an individual by extracting the image of an iris from the picked-up image of an eye of the individual.
2. Description of the Related Art
As an iris identifying apparatus which identifies an individual by extracting the image of an iris from the picked-up image of an eye of the individual, there is a so-called handheld type iris identifying apparatus which a target person to be picked up (hereinafter simply called “target person”) holds by a hand to pick up the image of an eye of that person.
The handheld type iris identifying apparatus has an infrared-sensitive image pickup unit located at the back of a cold mirror which passes infrared rays and an infrared illumination laid around the cold mirror.
There are a few guide lights over the cold mirror. The guide lights are on initially, and are all turned off when the image to be picked up comes into focus with the image pickup device inside the image pickup unit.
The target person turns his eyes on the guide lights first, and adjusts the distance between an eye and the iris identifying apparatus in such a way that the guide lights are all turned off. When the guide lights are all turned off, the target person keeps the iris identifying apparatus at the position. Then, the target person turns his eyes on the cold mirror and iris identifying apparatus picks up the image of the eye while viewing the image of the eye shown on the cold mirror.
A target person holds the handheld type iris identifying apparatus and turns his eyes on the guide lights, then adjusts the distance between an eye and the iris identifying apparatus in such a way that the guide lights are all turned off, and directs the line of sight to the cold mirror to pick up the image of the eye after confirming that all the guide lights have been turned off. It is difficult for a user, particularly, a novice to stably hold the position of the image pickup unit during image pickup.